Water lubricating system for steam-turbines.



No. 784,795. PATENTED MAR. 14, 1905. A. H. KRUESI.

WATER LUBRICATING SYSTEM FOR STEAM TURBINES.

APPLIOATION FILED SEPT.3. 1903.

2 SHEETSSHEET. l.

\ Witnesses: Inventor:

Jqu ust H.Kruesi, 5 W

PATENTED MAR. 14,1905. A. H. KRUESI. WATER LUBRICATINGSYSTEM FOR STEAM TURBINES.

2 SHBETSSHEET 2.

APPLICATION FILED SEPT.(% 1903.

Uu ID -IELLEEFEFEE L Witnesses:

UNITED STATES Patented March 14, 1905.

PATENT OFFICE.

, AUGUST H. KRUESI, OF SCHENECTADY, NEIV YORK, ASSIGNOR TO GEN- ERAL ELECTRIC COMPANY, A CORPORATION OF NEIV YORK.

WATER LUBRICATING SYSTEM FOR STEAM-TURBINES.

SPECIFICATION forming part of Letters Patent No. 784,795, dated March 14, 1905.

Application filed September 3, 1903. Serial No. 171,757.

[ all whom, it TIMLZ/ concern.-

Be it known that I, Anensr H. KnUnsI, a citizen of the United States, residing at Schenectady, in the county of Schenectady and State of New York, have invented certain new and useful Improvements in \Vater Lubricating Systems for Steam-Turbines, of which the following is a specification.

This invention relates to steam-turbines, and especially to those in which the rotating shaft is surrounded by a vacuum-chamber into which the steam exhausts from the buckets, saidchamber containing a vacuum due to the condenser. In such an engine if the shaftbearing is located outside of said chamber there must be a vacuum-tight packing for the shaft where it passes out of the chamber. If the bearing is inside the chamber, there is a constant tendency for the fluid lubricant to escape from the bearing and mingle with the exhaust-steam, and if the lubricant is oily it causes trouble in the condenser and boiler. To avoid this objection, I propose to use water as a lubricant for the step-bearing, so that the leakage will simply mingle with the steam and pass on into the condenser.

In all condensing systems it is necessary to introduce constantly a small quantity of water to compensate for the loss by leakages and also to compensate for the steam used by auxiliaries where they exhaust into the atmosphere. This make-up water is usually from two to five per cent. of the total amount circulating through the system, and as this quantity is just about what is necessary to keep the step-bearing properly lubricated it is possible, therefore, to take the water for the stepbearing directly from the main water-supply. I prefer, however, to take itfrom the hot-well of the condenser either directly or from the boiler feed-tank, which is fed from the hotwell by a low-pressure pump.

In the accompanying drawings, Figure 1 is a diagrammatic illustration of a boiler, turbine, condenser, and pumps embodying my invention. Fig. 2 similarly illustrates a modiiication, and Fig. 3 shows a further modification.

The turbine may be of any suitable type,

the one shown being the Curtis. The bucketwheel 1 is mounted on the vertical shaft 2, which is inclosed in the exhaust chamber formed by the hollow base 3. The shaft rotates in a step and guide bearing 1, which is set up into the base from below and secured by a steam and air tight joint. To lubricate this bearing, water is forced into it under heavy pressure through a pipe 5 by means of a highpressure pump 6. The exhaust-steam from the buckets flows out of the base 3, through a pipe 7, into a surface condenser 8 of any suitable construction, and the water of condensation gravitates into a hot-well 9. A-dry-air pump 10 is connected with the bottom of the condenser, the air and vapor being drawn through a cooler 11 to facilitate the operation of the pump. The make-up water or part of it passes through a coil in the cooler and thence into the hot-well. This pump and cooler are broken away in Fig. 2. From the bottom of the hotwell the hot water is fed back to the boiler 12, which supplies steam through a pipe 13 to the nozzles or other discharging device of the turbine. The water may be forced into the boiler directly by a centrifugal pump 14, or it may be pumped by a lowpressure pump 15 into a feed-tank 16, from which a high-pressure pump 17 forces it into the boiler. Fig. l showsa feed-water heater 18 fed from the tank 16 by a pump 19 and supplying the pump 17.

The pump 6 is a high-pressure pump of special design, effecting a continuous steady flow of water to the step-bearing 1. The particular means by which this is accomplished forms no part of the present invention, and therefore needs no detailed description. The steady flow is necessary in order to maintain an even lubrication of the bearing, which would not be possible with the pulsating delivery of an ordinary pump.

In Fig. 1 the pump 6 is so located that the water in the hot-well will fiow to it by gravity. In very many instances, however, the pump has to be placed higher than the hotwell, in which case it cannot lift the water owing to the vacuum in the condenser. It then becomes necessary touse a low-pressure pump 20, Fig. 2, taking water by gravity from the hot-well and lifting it to a tank 21, from which it will flow by gravity to the pump 6. In this system the make-up water is fed into thefeedtank 21 through a pipe 22. A relief-valve 23 permits an overflow from the tank in case the pump 20 or the make-up pipe 22 feeds the water faster than the pumps 6 and 17 draw it off.

Fig. 3 shows a tank at, supplied with water from a main 25 and supplying the pump 6.

In Fig. '1 the make-up water enters the system through the cooler in Fig. 2 through the feed-tank and in Fig. 3 through the highpressure pump 6. In Figs. 1 and '2 the lubricating-water is taken wholly from the hotwell, which is an advantage in that the air and gases have been removed by the air-pump, leaving a denser fluid without adding or subtracting water to or from the system. The make-up water entering through the cooler or the pipe 22 brings in a small amount of air; but only a small part of this will pass through the pump 6. In Fig. 3 all the air in the make-up water is forced through the stepbearing. 1 n case the amount of water required by the bearing is greater than that of the necessary make-up water the excess may be discharged by a relief-valve.

It is evident that since two high-pressure pumps 6 and 17 are used it would be possible to substitute a single pump to do the work of both; but I prefer the arrangement shown.

Figs. 1 and 2show closed systems wherein the make-up water is used as a lubricant. Hence the amount of air introduced into the system is small and the tendency to impair the vacuum is slight. In case the amount of water necessary for lubricating purposes exceeds the demand for make-up water a suitable relief-valvc may be employed to dis charge the excess into a tank after it passes through the bearing.

In accordance with the patent statutes I have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by other means.

WVhat I claim as new, and desire to secure by Letters Patent of the United States, is

1. In a steam-turbine, the combination with a base COlItitll'llUg an exlmust-chamber, of a condenser connected with said chamber, a shaft-bearing supporting the entire weight of the n'ioving element and located in said chamber which bearing is subjected to the action ofthc condenser, and means for supplyingsaid bearing with water for lubrication.

2. In a steam-turbine, the combination with a shaft-bearing d ischarging water into the condenser where it mingles with the exhaust from the turbine, of a condenser, and a pump supplied with water from said condenser and forcing it into said bearing to lubricate the same. 4

3. In a steam-turbine, the combination with a step-bearing located in the exhaust-passage, of a condenser, and a pump receiving water from the hot-well of the condenser and forcing it into the step-bearing to lubricate the same.

4:. In a steam-turbine, the combination with a step-bearing located in the exhaust-passage, of a condenser, a feed-tank, a pump forcing water from the hot-well into the feed-tank, and a pump taking water from the tank and forcing it into the step-bearing.

5. In a steam-turbine, the combination with a step-bearing located in the exhaust-passage, of a condenser, a pump receiving water from said condenser and forcing it into said bearing, and means for adding make-up water to the system.

6. In asteam-turbine, the combination with a step-bearing located in an exhaust-passage. of means whereby make-u p water for the condenser system is fed to said bearing.

7. An elastic-fluid turbine comprising a chamber and a shaft-bearing which supports the entire weight of the moving structure and is closed to the atmosphere and discharges its lubricant into the chamber where it mingles with the exhaust from the turbine, in combination with a condenser which maintains a vacuum in the chamber, and a pump for supplying l'luid to the bearing under high pressure. Y

8. In an elastic-fluid turbinehaving a shaftbearing which is closed to the atmosphere, a condenser, a vaporizer, and a pump for supplying make-up liuid to the vaporizer through the bearing.

9. In combination, an elastic-fluid turbine comprising a frame containing an exhaust-receiving chamber, and a shaft-bearing in the chamber, a vapor-generator for supplying vapor to the turbine, means for conveying condensed vapor to the vaporizer, and a conduit which supplies liquid to the bearing for lubricating it and also to the vaporizer through the bearing.

10. In combination, an elastic-fluid turbin comprising a frame containing an exhaust-receiving chamber, and a shaft-bearing located in and discharging into the chamber, a vaporgel'ierator for supplying vapor to the turbine, a condenser connected to the chamber and vaporizer, a means for forcing liquid from the condenser to the vaporizer, a dry air pump connected to the condenser, and a conduit for supplying liquid under pressure to the bearing for lubricating it.

11. In combination, an elastic-fluid turbine comprising a frame containing an exhaustchamber, and a sha'ft-bearii'ig located in and discharging into the chamber, a vapor-generator for supplying vapor to the turbine, a condenser eonnected to the exhaust-chamber, a hot-well receiving water from the condenser,

IO closed system, a bearing for the turbine-shaft Which is subjected to and discharges into the condenser, and a conduit which supplies lubricating fiuid to the bearing and make-up liquid to the system.

In Witness whereof I have hereunto set my 5 hand this 1st day of September, 1903.

AUGUST H. KRUESI. Witnesses:

BENJAMIN B. HULL, HELEN ORFORD. 

